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Dwyer Instruments, Inc.1950 Explosion Proof Differential Pressure Switches

Specifications
Ordering information
1950 Series Pressure Switch Compact, low cost, explosion-proof and weatherproof. The 1950 series pressure switch is U.L. and C.S.A. listed, FM approved for use in Class I, Groups C and D, Class II Groups E, F and G and Class III hazardous atmospheres (NEMA 7 and 9). Weather-proof features include a drain plug and O-ring seal in cover. Electrical connections are easily made by removing front cover. For convenience the set point adjustment screw is located on the outside of the housing. Twelve models offer set points from 0.03 to 20 inches of water and from 0.5 to 50 PSI. The unit is very light and compact - about half the weight and bulk of other explosion-proof or weather-proof switches with separate enclosures. 
 

Specifications

Temperature Limits: -40°F to 140°F 
0°F to 140°F for 1950P-8, -15, -25 and -50 
-30°F to 130°F for 1950-02
Maximum Surge Pressure:  1950 - 10 PSI 
1950P - 50 PSI 
1950P-50 only - 90 PSI
Rated Pressure: 1950 - 45"WC 
1950P - 35 PSI 
1950P-50 only - 70 PSI
Pressure Connections: 1/8" FNPT
Electrical Rating: 15 amps, 125, 250, 480 volts, 60 Hz. A.C. 
resistive; 1/8 H.P. @ 125 volts, 
1/4 H.P. @ 250 volts, 60 Hz. A.C.
Wiring Connections: 3 screw type; common, normally open 
and normally closed
Conduit Connection: 1/2" NPT
Set Point Adjustment: Screw type on top of housing; field adjustable
Housing: Anodized cast aluminum
Diaphragm: Moulded fluorosilicone rubber - Optional Buna-N or Viton (R) available. 
02 model - silicone on nylon
Calibration Spring: Stainless steel
Installation: Mount with diaphragm in vertical position
Weight: 3¼ lbs.; 02 model - 4 lbs, 7oz.
Caution: For use only with air or compatible gases. Applications with hazardous atmospheres
and a single positive pressure may require special venting.
Viton (R) is a registered trademark of Dupont Dow Elastomers

Ordering Information

Model Number Range (inches of water)
1950-02 0.03 to 0.10
1950-00 0.07 to 0.15
1950-0 0.15 to 0.50
1950-1 0.4 to 1.6
1950-5 1.4 to 5.5
1950-10 3 to 11
1950-20 4 to 20
Model Number  Range (PSID)
1950P-2 0.5 to 2
1950P-8 1.5 to 8
1950P-15 3 to 15
1950P-25 4 to 25
1950P-50 15 to 50


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1641 Venables Street
Vancouver, British Columbia, Canada
V5L 2H1

Phone: 604-254-9622
Fax: 604-254-3123

e-mail: info@johnsherman.com